1. Field of Invention
The invention relates to an internal combustion engine including a combustion chamber for combusting a fuel in an explosion cycle, and a pump chamber which is connected with the combustion chamber and which is filled with a pump liquid through a liquid inlet opening, with the pump liquid being expelled from the liquid outlet opening under the action of the combustion gas formed in the explosion cycle.
2. Description of the Prior Art
A combustion engine of the type discussed above is known, for example, from the WO 98/01338. In the known internal combustion engine, a plurality of pump chambers, from which the pump liquid is expelled under the direct action of the inflowing combustion gas, is assigned to a single combustion chamber.
An object of the present invention is to improve the efficiency of the internal combustion engine of the type discussed above.
This and other objects of the present invention which will become apparent hereinafter, are achieved by dividing the pump chamber by a flexible diaphragm into a gas chamber and a liquid chamber.
Because of the division of the pump chamber with a flexible diaphragm into a gas space and a liquid space, there can be no mixing between the combustion gas and the pump liquid, which would have lead to a decrease in efficiency. Furthermore, the combustion gas is not divided among several pump chambers, as a result of which the overall construction can be simplified.
Under the action of the combustion gas flowing out of the combustion space, the diaphragm is displaced from its first operational position, in which the liquid chamber takes up essentially the whole volume of the pump chamber, into its second operational position, in which the gas space occupies essentially the whole volume of the pump chamber, with the pump liquid being forced out of the outlet opening of the space chamber. In a subsequent implosion cycle, a cooling liquid can be sprayed with a spraying device into the gas space of the pump chamber, as a result of which, because of the cooling of the hot combustion gas, a reduced pressure is produced in the pump chamber, whereby the diaphragm is pushed in the direction of its first operational position, and a new charge of pump liquid can be pumped into the liquid space of the pump chamber. Due to the spraying of cooling liquid into the pump chamber, the surface of the diaphragm, facing the gas space, can furthermore advantageously be wetted with cooling liquid, and a film, which protects the diaphragm against the high temperature of the combustion gas, can be formed.
The division of a pump chamber into the gas space and the liquid space can be accomplished by a single elastic diaphragm or by several elastic diaphragms, which are formed, for example, in the form of a tube.
Advantageously, the combustion chamber forms part of a circuit for the pump liquid and which also includes a turbine. In a particularly preferred embodiment, this turbine is a radial turbine.
Advantageously, an interim reservoir, which can be filled with pump liquid and emptied in the implosion cycle, is connected with the outlet of the turbine. Due to the use of such an interim reservoir, which in timed fashion can be filled with liquid or emptied of liquid, the total volume of pump liquid can be decreased significantly in contrast to the known oscillating liquid circuit disclosed in the WO 98/01338 and, accordingly, a significantly smaller, lighter and more rapidly reacting combustion engine can be produced.
Advantageously, the liquid flows essentially radially not only in the turbine, but also in the pump chamber and/or in the interim reservoir, as result of which a low overall height and, with that, a high, maximum attainable number of cycles of the engine can be obtained.